XC61H Series
■NOTES ON USE
1. Please use this IC within the stated maximum ratings. The IC is liable to malfunction should the ratings be exceeded.
2. When a resistor is connected between the VIN pin and the input with CMOS output configurations, irregular oscillation
may occur as a result of voltage drops at RIN if load current (IOUT) exists. It is therefore recommend that no resistor be
added. (refer to Figure 1 below)
3. When a resistor is connected between the VIN pin and the input with CMOS output configurations, irrespective of N-ch
output configurations, oscillation may occur as a result of shoot-through current at the time of voltage release even if
load current (IOUT) does not exist. (refer to Figure 1 below)
4. By connecting a resistor between the VIN pin and the input, detect and release voltages will rise as a result of the IC's
supply current flowing through the VIN pin.
5. If a resistor (RIN) must be used, then please use with as small a level of input impedance as possible in order to control
the occurrences of oscillation as described above.
Further, please ensure that RIN is less than 10kΩ and that CIN is more than 0.1μF (Figure 1). In such cases, detect
and release voltages will rise due to voltage drops at RIN brought about by the IC's supply current.
6. Depending on circuit's operation, release delay time of this IC can be widely changed due to upper limits or lower limits
of operational ambient temperature.
●Irregular Oscillations
(1) Irregular oscillation as a result of output current with the CMOS output configuration:
When the voltage applied at IN rises, release operations commence and the detector's output voltage increases.
Load current (IOUT) will flow through RL. Because a voltage drop (RIN x IOUT) is produced at the RIN resistor, located
between the input (IN) and the VIN pin, the load current will flow via the IC's VIN pin. The voltage drop will also lead to
a fall in the voltage level at the VIN pin. When the VIN pin voltage level falls below the detect voltage level, detect
operations will commence. Following detect operations, load current flow will cease and since voltage drop at RIN will
disappear, the voltage level at the VIN pin will rise and release operations will begin over again.
Irregular oscillation may occur with this "release - detect - release" repetition.
Further, this condition will also appear via means of a similar mechanism during detect operations.
(2) Irregular oscillation as a result of shoot-through current:
Since the XC61H series are CMOS ICS, shoot-through current will flow when the IC's internal circuit switching
operates (during release and detect operations). Consequently, irregular oscillation is liable to occur during release
voltage operations as a result of output current which is influenced by this shoot-through current (Figure 3).
Since hysteresis exists during detect operations, irregular oscillation is unlikely to occur.
XC61HC Series
XC61HN Series
図 1．入力抵抗を入れた時の回路例
Figure 1 Use of input resistor RIN
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TOREX [ Torex Semiconductor ]
